that traditional paper filters do not fit all that snugly in the air intake compartment. They've improved, but they're still not great. More importantly, though, they let way too much debris shoot right through the filter element itself. As a side-note, they do not provide for very good air flow either.

You see, as a compromise to allow enough air flow for your engine to run "properly", surface type air filtration media have to allow certain sized particles to flow through. If they made the filtration media any more tightly woven, not enough air would pass through quickly enough to keep your vehicle running.

As a result, most paper filters won't catch anything smaller than about 20 to 40 microns with any real efficiency. In most cases, the more expensive the filter, the lower the micron level of filtration - and the lower the better, of course.

20 to 40 microns is pretty small. A human hair is about 100 microns in diameter. The problem is that 60% of engine wear is caused by particles between 5 and 20 microns (most likely because there is so much more of it). If you don't keep that stuff out, it'll eat away at your engine.

Consider an alternative air filtration device which is more like a sponge (actually, it's foam). Because foam is "squishy" it can be made slightly larger than the air intake compartment so that when installed it fits very snug with no room for air to by-pass the filtration unit.

In addition, it has millions of "tiny" channels through which air can flow, but these channels are not straight channels. They twist and turn through the filtration media. Air can pass through easily because these "tiny" channels are actually much larger than the channels through the paper filter we just discussed. This is possible because the paper filter only has one chance to get the dirt. This foam media has multiple opportunities to catch the dirt.

You see, as the air travels through these winding channels, it can turn this way and that with ease. However, the dirt particles that the air is carrying travel in a straight line until they hit something. Obviously, at every turn, the debris within the air hits a "wall". You say, "Well, that's great, but why doesn't that dirt just bounce off the wall and keep right on going?" Good point. I tell you what, why don't we put a tacky substance in the foam so that when debris hits these "walls" it's stuck there like a fly to one of those sticky tapes. You say, "Yeah, that would work!"

Not only will it work, it will work far better than the paper air filter discussed above. Because of the depth-type nature of the foam filter AND the added tack oil, it will remove most particles larger than 5 to 10 microns. Thus, most of the harmful stuff is stopped before it ever reaches the inside of the engine.

Now, we've established that such a filtration media would seal up the intake compartment, should have better air flow, and we've established that it has more opportunities to catch the dirt, so probably less dirt makes it into the engine. The next question should be, will it hold as much dirt as the paper filter?

Well, of course it will. It's much thicker than a paper filter, and, because of the nature of the foam media, has a virtually limitless surface area over which to collect dirt. In fact, the more dirt it collects, the better the filtration (with minimal reduction in air flow). It's also much more durable than paper, so it NEVER needs to be replaced. Just wash it once a year, re- oil it and put it back in the vehicle.

 

What year Evo or Evo MAF was it they used, because I've had very interesting observations about the freakin oil and my 03' Evo since, well, 03'. Too much oil equals me having to break out the electronics cleaner for sure.

 

When I replaced my stock filter with the Buschur filter I had to clean the MAF up. After running the Buschur filter for about a year and a half the MAF has yet to get dirty again.

 

After sending an e-mail to Blackstone concerning the air filtration issue this was there response:

Thanks for the e-mail. You can get silicon in the oil from anti-freeze, though without any significant potassium or sodium present, we doubt that's the source. If the air filter is clean and there are no problems with the air induction system (like cracks downstream of the air filter), then that's not like the source. Silicon can also come from silicone products like sealers and spray lubricants and these are harmless. Let me know if you have any more questions.
I had cams installed 2 months after the oil change. When they put everything back together they could have over used silicone sealers.

 

I don't work for K&N but this is an interesting read:
http://www.knfilters.com/MAF/massairfindings.htm
http://www.knfilters.com/MAF/MAFTestresults.htm

 

Very interesting, worth looking into.